JP2011167837A - Circular saw blade with cutting tips mechanically locked against multiple force vectors - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a circular saw blade including a substantially planar body having: an essentially circular periphery in which a plurality of annularly spaced tip support portions; and a plurality of cutting tips affixed by brazing to the tip support portions of the body are formed. <P>SOLUTION: Each cutting tip 48 has a mounting base formed with at least two locking surfaces 48d, 48e along which the brazing affixes the mounting base to the respective tip support portion 44. The locking surfaces are configured and located in relation to one another and to the body for counteracting forces which act against the cutting tip in differing directions in the plane of the body 48a during rotational cutting operation of the blade. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates generally to circular saw blades, and more particularly to a circular saw blade in which typically a cutting tip of carbide material is typically secured by brazing around the circumference of the body of the saw blade. About.

  Circular saws are well known and widely adopted in architecture, wood processing and similar industries. Such circular saws come in a variety of types ranging from large stationary devices, such as those sometimes referred to as tables, to portable handheld saws. All such circular saws typically use a circularly supported circular saw blade in conjunction with a drive motor that is driven about a central axis. Circular saw blades generally have a substantially flat main body with an essentially circular circumference, around which a number of cutting teeth are spaced and the saw blade is driven to rotate The tooth performs a cutting operation on wood or other material to which the blade is applied.

  The main body of the circular saw blade is typically made from a hardened metal alloy, most commonly a hardened steel alloy. The cutting teeth of the circular saw blade can be formed integrally as part of the periphery of the main blade body, or chips of various hard materials firmly fixed around the main body, for example by brazing Can be in the form of Most commonly, saw blade cutting tips with tips are made from carbide materials because of their high hardness and improved ability to maintain sharp edges over extended periods of use. The use of cutting tips also typically indicates that more types of cutting blade shapes and geometries are utilized than is possible with cutting teeth formed integrally with the main body of the saw blade. enable.

  Although the placement of the cutting tip provides these stated advantages, the use of the cutting tip also resists loosening or disengagement under the influence of different forces acting on the tip in different directions during the cutting operation. Presents the challenge of ensuring that it is firmly fixed to the blade body. Various proposals have been made in the industry to address this problem. For example, US Pat. No. 5,794,503 proposes a special tip shape intended to increase the strength of the connection by brazing the tip to the main blade body. This development still has drawbacks. First, this tip shape is not compatible with typical conventional brazing devices, thereby requiring a special brazing machine to achieve the intended connection of the tip to the blade body. Secondly, the tip shape is only effective in resisting substantially tangential forces around the blade periphery when secured to the blade body, and does not resist substantially radial forces.

  Thus, a tip shape that can be fixed using existing conventional brazing devices and that is effective to counteract the forces acting on the saw blade in various directions, particularly in both radial and tangential directions There is a continuing need for improved saw blades in the industry.

  Briefly summarized, the present invention basically consists of (a) a substantially flat main body having an essentially circular periphery on which a plurality of annularly spaced tip supports are formed, and ( b) Essentially any saw blade can be used as long as it is a circular saw blade including a plurality of cutting tips fixed to the tip support portion of the main body by brazing. In accordance with the present invention, each cutting tip has a mounting base formed with at least two locking surfaces, and brazing along these locking surfaces secures the mounting base to the respective chip support. Form at least two mechanical locks on the chip. The locking surfaces are shaped and positioned relative to each other and to the main body to counteract numerous forces acting on the cutting tip in different directions in the plane of the main body during the rotary cutting operation of the blade. Yes. Advantageously, the cutting tip of the present invention can be secured to the main body using a conventional brazing device.

  It is believed that various configurations and embodiments of the present invention are possible. For example, but not limited to, one of the locking surfaces can include a recessed region within the mounting base of the cutting tip, while another locking surface can include a protruding region within the mounting base of the cutting tip. The recessed area can include a curved recess in the mounting base of the cutting tip, for example a circular recess having a radius of about 0.2 mm or more. The protruding region can include a curved protrusion in the mounting base of the cutting tip, for example a circular protrusion having a radius of about 0.2 mm to about 1.0 mm. As used herein, the term “curved” means any spreading surface formed from any combination of curved and / or linear surfaces that collectively form concave recesses or convex protrusions. And is intended to be included.

  Each cutting tip includes a cutting edge. In many possible embodiments, it is preferred that the two locking surfaces be arranged substantially opposite the cutting edge. Each tip support has two locking surfaces configured to mate with the locking surface of the respective cutting tip, such as a recess such as a curved recess in the tip support that receives the protrusion and recess area of each cutting tip. It is advantageous to include protruding regions such as regions and curved convexities.

FIG. 1 is a fragmentary side view of a circular saw blade having a plurality of peripheral cutting teeth according to one known form of prior art structure.

FIG. 2 is another fragmentary side view similar to FIG. 1 of a circular saw blade having a plurality of peripheral cutting teeth according to another known form of prior art structure.

FIG. 3 is another fragmentary side view of a circular saw blade having a plurality of peripheral cutting teeth according to the present invention.

4A is an enlarged fragmentary perspective view of one cutting tip at one tip support location of the circular saw blade of FIG.

4B is an enlarged fragmentary perspective view of one cutting tip at one tip support location of the circular saw blade of FIG.

5 is a side view of the cutting tip and tip support location of FIG. 4 with the tip brazed to the support location.

  Referring to the accompanying drawings, initially FIGS. 1 and 2, two different forms of known prior art circular saw blades are shown. In FIG. 1, the saw blade is indicated generally by the reference numeral 10 and is separated around the circumference of the body 10 separated by interposing a peripheral recess 16 commonly referred to as a gullet. A main flat blade body 12 having a plurality of tip support portions 14 spaced apart from each other. Each chip support portion 14 of the blade body 12 is formed with a groove 18 configured to taper inwardly. Each of the plurality of hardened carbide cutting tips 20 is attached to the tip support portion 14 by brazing so as to be received in the groove 18 via a shaft portion 20 a having a shape complementary to the groove 18. An edge extending radially outward of the tip 20 is sharp to form a cutting edge 20b.

  In FIG. 2, a saw blade according to US Pat. No. 5,794,503 is indicated generally at 22. The saw blade 22 also includes a main flat blade body 24 having a plurality of tip supports 26 and a recess or blade groove 28 spaced therebetween around the periphery of the body 22. A plurality of quenched carbide cutting tips 30 are received in recesses 32 formed in the tip support 26, respectively. Each tip 30 has a shank 30a received within a respective recess 32 and a cutting edge 30b extending beyond the end of the recess 32 and beyond the tip support 26. The shaft portion 30a of each tip is formed with a flange 30c on one side thereof, which contacts the side surface of the tip support portion 26 of the blade body 24. The flange 30c is intended to provide an increased amount of surface area for brazing the tip 30 to the blade body 24 so as to provide a mechanical connection of the tip 30 to the blade body 24.

  In each case of the prior art saw blades of FIGS. 1 and 2, the configuration of the cutting tip with respect to the recess to which the tip is fixed has a mechanical locking effect that is effective against forces acting in only one direction. It will be appreciated and understood by those skilled in the art to provide a unique form. Furthermore, in each form of the saw blade, these tips are difficult to braze to the blade body using conventional industrial brazing equipment.

  Referring to FIGS. 3-5, a saw blade according to the present invention is indicated generally at 40. The saw blade 40 basically comprises a substantially flat main body 42, preferably formed from a sheet metal of hardened steel alloy, which has an essentially circular perimeter, which includes a corresponding plurality of A plurality of annularly spaced tip supports 44 spaced apart from each other by a recess or blade groove 46 are formed. Each cutting tip 48 is fixed to the front edge 44a in front of each tip support portion 44, preferably by brazing (when viewed in the direction of rotation of the saw blade indicated by the arrow direction in FIG. 3).

  In contrast to the saw blades of FIGS. 1 and 2, each tip support 44 and each cutting tip 48 are of a special novel interlocking shape that provides at least two locking surfaces, Along with brazing, the tips 48 are secured to their respective tip supports 44. More specifically, as best seen in FIGS. 4A, 4B and 5, each cutting tip 48 has a main body 48a that forms a mounting base, which has a sharp cutting edge 48b at one end of the main body 48a. The main tip body 48a is centrally along its length and substantially opposite the cutting edge 48b, in this embodiment in the form of a curvilinear concave recess, preferably a circular recess with a radius in the range of about 0.2 mm or more. The recess 48d is formed. Further, the end of the main tip body 48a opposite the cutting edge 48b is in the form of a curved convex protrusion in this exemplary embodiment, preferably a circular convex protrusion with a radius of about 0.2 mm to about 1.0 mm. A portion 48e is formed.

  Similarly, the leading edge 44a of each tip support 44 is adjacent to its radially outermost edge, and in this example shown, has a curved convex shape that substantially engages the curved concave recess 48d of the cutting tip 48. A protrusion 44d in the form of a protrusion is formed. The front edge 44a of each tip support 44 further includes a shoulder 44c in the illustrated example in which a recess 44e in the form of a curved recess substantially mating with the curved protrusion 48e of the cutting tip 48 is formed. Are formed radially inwardly and spaced along it. The main body 48a of each cutting tip 48 is preferably of a size slightly wider than the lateral thickness of the blade body 42, thereby providing a lateral relief of the cutting body 48 of each cutting tip 48, which is the tip. This facilitates the brazing of the 48 chip supports 44.

  When the tip 48 is brazed to the main blade body 42, the brazing follows the shape of the main tip body 48a, in particular according to the engagement recesses and projections 44d, 48d and 44e, 48e. In this embodiment, the recesses and protrusions 44d, 48d and 44e, 48e act as locking surfaces, which together with brazing form multiple mechanical connections for each respective cutting tip 48. Respective different relative configuration shapes (concaves or other recesses and protrusions or other protrusions) and the relativeities of the side and end recesses and protrusions 44d, 48d and 44e, 48e of each chip 48 Due to the correct position, the locking surfaces formed by the mating recesses and projections 44d, 48d and 44e, 48e are in different directions in the plane of the main blade body with respect to the cutting tip during the rotary cutting operation of the saw blade. It is extremely effective against each other because it counteracts the acting forces. For example, as schematically shown in FIG. 5, the mechanical lock created by the recesses and projections 44d, 48d and 44e, 48e is against both radially inward and outward force vectors. And acts against the tangential force vectors and against the inward and outward force vectors in the angular direction between them. In addition, since the brazing of the tip 48 to the main blade body 42 only follows the edge of the main tip body 48a in the plane of the blade body 42, the tip 48 can be used in a conventional manner without the need for special machinery or accessories. It can be brazed without difficulty using industrial standard brazing equipment.

  Although the saw blade of the present invention has been described and illustrated herein with reference to a preferred embodiment in which the cutting tip has a special grooved shape with concave recesses and convex protrusions, it should be understood that the present invention is not so limited. It will be understood by the vendor. Instead, the cutting tip according to the invention reacts against a number of forces acting on the cutting tip in different directions in the plane of the blade body during the cutting operation when brazed to the tip support of the saw blade body. It should be understood that a variety of other shapes with multiple locking surfaces in position and position can be included to form multiple mechanical locks that are effective relative to one another. Accordingly, the present invention is to be construed and interpreted as including all such embodiments and is limited to the specific chip shapes shown in the drawings and described above which are merely exemplary of the invention. Should not.

  Therefore, it will be easily understood by those skilled in the art that the present invention can be widely used and applied. Many embodiments and adaptations of the invention other than those described herein, as well as many variations, modifications, and equivalent arrangements, can be made without departing from the spirit or scope of the invention. Will be apparent or justified from the description. Thus, although the invention herein has been described in detail with reference to preferred embodiments thereof, this disclosure is merely illustrative and exemplary of the invention and is made merely for the purpose of providing a complete and possible disclosure of the invention. It should be understood that The above disclosure is not intended or should be construed as excluding such other embodiments, adaptations, alterations, modifications, and equivalent arrangements that are not intended or limited to the invention. The invention should not be limited only by the claims appended hereto and their equivalents.

Claims (12)

A substantially flat main body having an essentially circular perimeter formed with a plurality of annularly spaced tip supports, and a plurality of cuttings secured to the main body chip supports by brazing Chips,
A circular saw blade including
Each cutting tip has a mounting base formed with at least two locking surfaces, and brazing along these locking surfaces secures the mounting base to the respective chip support to provide at least two respective mechanical locks. Formed on top of each other and on the main body to counteract the numerous forces acting on the cutting tip in different directions in the plane of the main body during this rotary cutting operation of the blade Circular saw blade characterized by being and being positioned.   The circular saw blade according to claim 1, wherein one of the locking surfaces includes a recessed area in the mounting base of the cutting tip.   3. A circular saw blade according to claim 2, wherein the recessed area includes a curved recess in the mounting base of the cutting tip.   4. The circular saw blade according to claim 3, wherein the curved recess has a radius of about 0.2 mm or more.   The circular saw blade according to claim 1, wherein one of the locking surfaces includes a protruding region in the mounting base of the cutting tip.   The circular saw blade according to claim 5, wherein the protruding region includes a curved convex portion in the mounting base of the cutting tip.   The circular saw blade according to claim 6, wherein the convex portion of the curve has a radius of about 0.2 mm to about 1.0 mm.   The circular saw blade according to claim 1, wherein each cutting tip includes a cutting edge, and two rocking surfaces are disposed substantially opposite the cutting edge.   2. A circular saw blade according to claim 1, wherein each tip support includes two locking surfaces that engage the locking surfaces of the respective cutting tip. A substantially flat main body having an essentially circular periphery, wherein a plurality of annularly spaced tip supports and a plurality of recessed blade grooves between the tip supports are alternately formed; and A plurality of cutting tips fixed to the tip support portion of the main body by brazing, each cutting tip having a mounting base for fixing to the respective tip support portion and a cutting edge substantially facing an adjacent blade groove thing,
A circular saw blade including
Each tip support has at least two locking surfaces, the mounting base of each cutting tip has at least two locking surfaces that engage the locking surface of the respective tip support, and brazing along the tip support has a mounting base. Fixed to each chip support, forming at least two respective mechanical locks thereon,
One of the locking surfaces of each chip support includes a curved recess recessed therein, and another of the locking surfaces of each chip support includes a curved protrusion protruding therefrom,
One of the locking surfaces of the mounting base of each cutting tip includes a curved recess recessed in the mounting base of the cutting tip that mates with a curved convex portion of another locking surface of the respective chip support, and the mounting base of each cutting tip Another of the locking surfaces of the tip includes a curvilinear protrusion projecting from the mounting base of the cutting tip that mates with a curvilinear recess in one locking surface of each tip support;
Mechanical locks are positioned relative to each other and to the main body to counteract the forces acting on the cutting tips in different directions in the plane of the main body during the rotary cutting operation of the blades,
A circular saw blade characterized by that.   The circular saw blade according to claim 10, wherein the concave portion of the curve has a radius of about 0.2 mm or more.   The circular saw blade according to claim 10, wherein the convex portion of the curve has a radius of about 0.2 mm to about 1.0 mm.

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